Ah yes, but it's an official report. City limits sounds more like song lyrics to me!?
Perhaps if I include the text, it will help?
The title is Périmètre de la métropole, and then it has: Périmètre retenu: (and my translation which is ok, but just to help those answering): A large part of municipal services and infrastructure is managed by the Brihanmumbai Municipal Corporation, or BMC, which makes up India's richest municipal administration.
No, unless you have contra-indications, périmètre in such a context means "area".
(OK, I know that any mathematician will immediately argue, quite correctly, that perimeter is a length (2 pi r) and that area is, well, area (pi r squared). But area is what most French people mean by périmètre. Tell them to go back to school, not me.)